In scanning laser devices, laser light is reflected off one or more scanning mirrors to generate a scanning pattern. For example, in scanning laser projectors, images are projected onto surfaces by scanning laser light into a pattern with a scanning mirror, with individual pixels generated by modulating the laser light during the scan. Some scanning laser projectors use multiple scanning mirrors to scan the laser light into a pattern. For example, some scanning laser projectors use a first scanning mirror to provide for scanning in one axis of motion, while using a second scanning mirror to provides for scanning in another axis of motion.
One issue with scanning laser projectors is achieving good image quality at different projection distances. For example, it is desirable to for a scanning laser projector to have good image quality at both a relatively far projection distance and at a relatively close projection. Providing good image quality over a relatively wide range of projection distances facilitates the use of the scanning laser projector in different configurations and in different applications.
Unfortunately, some past scanning laser projectors have been limited in their ability to provide acceptable image quality over such a range of distances. For example, some scanning laser projectors have been unable to provide good image quality at the relatively short projection distances needed for some applications. These scanning laser projectors can have relatively high levels of distortion when used at relatively short projection distances, and thus can be unable to provide acceptable image quality in some configurations. Thus, there is a continuing need for devices and techniques that provide improved image quality in scanning laser projectors, and in particular, reduce distortions in projected images when projected onto surfaces at relatively short distances.